External ear canal cholesteatoma after ventilation tube insertion

External ear canal cholesteatoma after ventilation tube insertion

1. Vojnosanit Pregl 2012; 69(4): 363–366. VOJNOSANITETSKI PREGLED Strana 363
Correspondence to: Milanko Milojeviý, Military Medical Academy, Clinic of Otorhinolaryngology, Crnotravska 17, 11040, Belgrade, Ser-
bia. Phone: [phone]. E-mail: [email protected]
CASE REPORT
UDC: 616.28:089-06
DOI: 10.2298/VSP1204363D
External ear canal cholesteatoma after ventilation tube insertion and
mastoidectomy
Holesteatom spoljnjeg slušnog kanala posle umetanja aeracione cevþice i
mastoidektomije
Dragoslava Djeriü*, Milan B. Jovanoviü
†
, Ivan Baljoševiü
‡
, Srbislav Blažiü*,
Milanko Milojeviü
§
*Institute for Otorhinolaringology and Maxillofacial Surgery, Faculty of Medicine,
University of Belgrade, Serbia;
†
Department of Otorhinolaryngology, Clinical Hospital
Center Zemun, Zemun, Serbia;
‡
Department of Otorhinolaryngology, Mother and Child
Institute “Vukan ýupiü”, Belgrade, Serbia;
§
Clinic of Otorhinolaryngology, Military
Medical Academy, Belgrade, Serbia
Abstract
Introduction. Etiopathogenetically, there are two types of
chollesteatomas: congenital, and acquired. Numerous
theories in the literature try to explain the nature of the
disease, however, the question about cholesteatomas re-
main still unanswered. The aim of the study was to present
a case of external ear canal cholesteatoma (EEC) devel-
oped following microsurgery (ventilation tube insertion
and mastoidectomy), as well as to point ant possible
mechanisms if its development. Case report. A 16-year-
old boy presented a 4-month sense of fullness in the ear
and otalgia on the left side. A year before, mastoidectomy
and posterior atticotomy were performed with ventilation
tube placement due to acute purulent mastoiditis. Diagno-
sis was based on otoscopy examination, audiology and
computed tomography (CT) findings. CT showed an
obliterative soft-tissue mass completely filled the external
ear canal with associated erosion of subjacent the bone.
There were squamous epithelial links between the canal
cholesteatoma and lateral tympanic membrane surface.
They originated from the margins of tympanic membrane
incision made for a ventilation tube (VT) insertion. The
position of VT was good as well as the aeration of the
middle ear cavity. The tympanic membrane was intact and
of normal appearance without middle ear extension or
mastoid involvement of cholesteatoma. Cholesteatoma
and ventilation tube were both removed. The patient re-
covered without complications and shortly audiology re-
vealed hearing improving. Follow-up 2 years later, how-
ever, showed no signs of the disease. Conclusion. There
could be more than one potential delicate mechanism of
developing EEC in the ear with VT insertion and mas-
toidectomy. It is necessary to perform routine otologic
surveillance in all patients with tubes. Affected ear CT
scan is very helpful in showing the extent of choleste-
atoma and bony defects, which could not be assessed by
otoscopic examination alone.
Key words:
cholesteatoma; tympanic membrane, perforation; ear,
external; tomography, x-ray computed; reoperation.
Apstrakt
Uvod. Holesteatom spoljnjeg slušnog hodnika retko je
otološko oboljenje. Etiopatogenetski, razlikuju se dve vr-
ste holesteatoma: kongenitalni i steÿeni. Mada u literaturi
postoje brojne teorije koje pokušavaju da objasne prirodu
nastanka oboljenja, još uvek je otvoreno pitanje zašto se
holesteatom javlja. Cilj rada bio je da se prikaže sluÿaj
pojave holesteatoma spoljnjeg slušnog hodnika posle mi-
krohirurške intervencije (insercija aeracione cevÿice i ma-
stoidektomija) i da ukaže na moguýe mehanizme njegovog
razvoja. Prikaz bolesnika. Bolesnik, star 16 godina, ispi-
tivan je i leÿen zbog recidivirajuýeg akutnog otitisa. Godi-
nu dana kasnije, posle umetanja aeracione cevÿice i mas-
toidektomije, bez simptoma ponovne pojave infekcije, u
levom spoljnjem slušnom hodniku naen je holesteatom.
Na presecima kompjuterizovane tomografije (KT) tempo-
ralne kosti utvreno je da holesteatom u celini ispunjava
lumen spoljnjeg slušnog hodnika i da nema patološkog
procesa u šupljinama srednjeg uva. Holesteatom je nastao
zbog odlaganja predvienih kontrolnih pregleda. Kod
bolesnika je uraena reviziona operacija (mastoidektomija
i uklanjanje aeracione cevÿice), pri ÿemu je prikazani hole-
steatom spoljnjeg slušnog hodnika u celini odstranjen. Na

2. Strana 364 VOJNOSANITETSKI PREGLED Volumen 69, Broj 4
Djeriý D, et al. Vojnosanit Pregl 2012; 69(4): 363–366.
kontrolnim pregledima lokalni nalaz bio je uredan, sluh
normalan, a KT nalazi nisu ukazali na pojavu recidiva
oboljenja. Zakljuÿak. Pojava holesteatoma prikazanog
bolesnika znaÿajna je pri razmatranju patogeneze ovog
oboljenja. Holesteatom je nastao posle umetanja aeracio-
ne cevÿice, najverovatnije proliferacijom epitela sa ivica
incizije bubne opne u lumen spoljnjeg slušnog hodnika.
Meutim, mehanizami ovog procesa su kompleksni i
multifaktorijalne prirode.
Kljuÿne reÿi:
holesteatom; bubna opna, perforacija; mastoiditis; uvo,
spoljašnje; tomografija, kompjuterizovana,
rendgenska; reoperacija.
Introduction
First report of epithelial debris accumulation in the ex-
ternal ear canal was made in 1850 by Toynbee
1
. The term
external ear canal cholesteatoma (EEC) was introduced in
1893 by Scholefield
2
. We presented a case of EEC after a
ventilation tube (VT) insertion and mastoidectomy. It is a
demonstration of a direct relationship between the use of a
VT after mastoidectomy and the later development of canal
cholesteatoma.
Case report
A 16-year-old boy presented with a 4-month history of
a sense of fullness in the left ear and occasionaly otalgia on
the same side. A year before admission the patient was sub-
mitted to surgery on the left ear due to acute purulent mas-
toiditis. Mastoidectomy and posterior atticotomy were per-
formed with a ventilation tube (Tübingen-gold) placement.
The patient was treated with antibiotics and his recovery was
uneventful. On recall examination, microotoscopy was nor-
mal, as well as auditive and vestibular function.
On admission otoscopy examination revealed a com-
plete obliteration of the left external ear canal (Figure 1).
Pure tone audiogram showed left sided medium conductive
hearing loss. There was no otorrhea or vertigo. Threedimen-
sional multislice computed tomography (3D MSCT) showed
a circumferential soft-tissue mass completely filling the ex-
ternal ear canal with associated erosion of the subjacent bone
(Figure 2). A ventilation tube was clearly seen, with well
aeration. A tympanic membrane was intact and of normal
appearance without middle ear extension or mastoid in-
volvement of cholesteatoma (Figure 3). The middle ear os-
sicules were also unaffected.
Fig. 2 – Axial temporal bone computed tomography (CT)
image show the soft-tissue mass filling the external ear canal,
the superior (black arrowheads) and inferior (white
arrowheads) links with ventilation tube insertion; the mass
has caused erosion of the canal walls (black arrows)
Fig. 3 – Coronal temporal bone computed tomography (CT)
shows removal of mastoid cells, normal position of a
ventilation tube and intact middle ear cavity
Fig. 1 – The external auditory ear canal with obliterative
cholesteatoma

3. Volumen 69, Broj 4 VOJNOSANITETSKI PREGLED Strana 365
Djeriý D, et al. Vojnosanit Pregl 2012; 69(4): 363–366.
The patient underwent revision mastoidectomy surgery
and extirpation of a VT. Intraoperatively, we confirmed
normal findings in mastoid and middle ear cavities (Figure
4). Firstly, obliterative canal cholesteatoma was excised en
block and then we removed a VT. From the margins of the
tympanic membrane incision we noted a proliferation
squamous epithelium remnants skipted laterally forming a
connection with cholesteatoma. In the ear canal we also
found the signs of bony wall erosion, partcularly of the ante-
rior wall. A defect of meatal skin was excised and the ir-
regular eroded area was drilled. The bone turned to normal
and healthy canaloplasty. Gross examination revealed an
ovoid white shaped mass. Histopathology revealed stratified
squamous keratinizing epithelial sac (matriks) with poor by
developed perimatrix. Postoperatively, the patient was well.
The place of tympanic membrane incision and meatal skin
were spontaneosly healed within one week. Audiology
showed improving in hearing with minimal loss around 20
dB. The patient was reviewed regularly and 2 years later
showed no signs of the disease.
Fig. 4 – The tympanic membrane is normal and anterior
bony wall erosion (arrowheads) of the external ear canal is
present after removing cholesteatoma (note the intact canal
wall after mastoidectomy)
Discussion
There are several well-known mechanisms of develop-
ing of EEC following different otologic surgeries. Choleste-
atomas can occur in the anterior sulcus as a complication of
lateral graft tympanoplasty
3
. If the epithelium is trapped un-
der the vascular strip, the cholesteatoma will form more lat-
erally in the canal, along the posterior wall
4
. Secondary EEC
has been seen as a postoperative complication after mastoid
surgery and may result from entrapment of squamous
epithelial debris during the healing process
5
.
Cholesteatoma is considered a complication of a VT
placement when developes behind an intact drum or next to a
perforation at or near the site of the tube insertion, in the
mesotympanum or hypotimpanum
6
. There is some contro-
versy regarding the development of cholesteatoma following
middle ear VT placement. Cholesteatoma may arise as a di-
rect complication of a VT placement in a retraction pocket in
an atrophic and flaccid area in the drum that progresses to
the point of debris accumulation, as a result of shedding and
implantation of epithelial cells into the middle ear or due to
ingrowth of squamous epithelium from the perforation mar-
gin to undersurface of the drum
7, 8
.
Theoretically, conditions for the development of secon-
dary cholesteatoma are perfect both when a VT is in place
and when a perforation or atrophic scar remains at the im-
plantation site. Because such cholesteatomas have been not
encountered following myringotomy alone or mastoidectomy
procedure we cannot accept seeding or implantation theories.
Causative factor in our case could be reverse epithelial in-
growth from the incision margins to the undersurface of the
drum, directed and enhanced by the tube
’
s flanges. Another
possibility was mastoid infection stimulating changes in ear
drum. Indication of mastoidectomy and of tube placement
was usually chronic persistent middle ear effusion unrespon-
sive to medical therapy. But in our patient a VT insertion
was performed due to acute supurative mastoiditis. A bacte-
rial infection initially could cause erosion of the epithelial
layer and granulation tissue at the place of a VT and be
partly related to later canal accumulation of keratin debris.
But it is contradictory to EEC developed in an ear without
recurrent episodes of otorrhea in a so-called “dry” ear with-
out infection, as in case we presented. Most areas of focal at-
rophy or retraction are cosmetic and nonprogressive, related
to the absence of a fibrous middle layer of the tympanic
membrane at intubation site
9
. This becomes problematic
only rarely if progresses to a retraction pocket and onward to
cholesteatoma (more common with longterm tubes)
10
. As
spontaneous extrusion did not occurr, and because ventila-
tion was sufficient, intention to remove the tube was not re-
alised. We assumed that cholesteatoma may not develop ei-
ther in a retraction pocket, in an atrophic scar as the tym-
panic membrane was rather normal. We also hypothesed that
as mastoidectomy have performed, the pattern of epithelial
migration of external ear canal to outside could be influenced
by restoring the normal ventilation of the middle ear. Slower
migration rates have already been demonstrated in the infe-
rior wall in patients with ECC and cholesteatoma we pre-
sented was mostly at that site. It was similarly suggested that
it could be explained by hypoxic conditions due to poor
blood supply
11
.
The main symptom was progressive conductive hypo-
acusis and it may be related to occlusion of the external canal
by cholesteatoma plug in obliterative cholesteatoma of ECC
12
, but many cases can be remarkably silent or even asymp-
tomatic. The invasion of squamous tissue with periostitis
may explain chronic dull pain experienced by our patient.
However, acute severe pain found more frequent in keratosis
obturans
13
. A preoperative high-resolution temporal bone CT
is helpful whenever the surgeon suspects EACC eroding into
adjacent anatomic structures. Erosion involving more than
one EEC wall is typical
14
but EEC could be more extensive
than that suggested by clinical findings
15
. For localized small

4. Strana 366 VOJNOSANITETSKI PREGLED Volumen 69, Broj 4
Djeriý D, et al. Vojnosanit Pregl 2012; 69(4): 363–366.
lesions, treatment consists of frequent cleaning with de-
bridement of necrotic tissue. Deeper pockets can be managed
with canaloplasty by removing diseased skin and bone and
exteriorizing the recess.
Conclusion
Although tympanostomy tubes are safe and effica-
cious for most patients with refractory otitis media or mas-
toiditis, they are associated with significant sequelae like
cholesteatoma development. EEC is a rare entity after VT
insertion with characteristic imaging and clinical features
but different variables may influence its development. Ex-
act fine mechanisms of cholesteatoma forming in the exter-
nal ear canal near a tube placement site are still unknown.
It is necessary to perform routine otologic surveillance in
all patients with tubes. Affected ear CT scan is very helpful
in showing the extent of cholesteatoma and bony defects,
which could not be assessed by otoscopic examination
alone.
REFERENCES
1.Toynbee J. A specimen of molluscum contagiosum developed in
the external auditory meatus. Lond Med Gaz 1850, 46: 261î4.
2.Schofield RE. Cholesteatoma of auditory canal caused by a bug.
Lancet 1893; 2: 929.
3.Plester D, Pusalkar A. The anterior tympanomeatal angle: the
aetiology, surgery and avoidance of blunting and annular cho-
lesteatoma. Clin Otolaryngol Allied Sci 1981; 6(5): 323î8.
4.Venkatraman G, Mattox DE. External auditory canal wall cho-
lesteatoma: a complication of ear surgery. Acta Otolaryngol
1997; 117(2): 293î7.
5.Graham MD, Larouere MJ. Miscellaneous external auditory canal
problems. In: Brackmann DE, Shelton C, Arriaga MA, editors.
Otologic surgery. Philadelphia: WB Saunders; 1994. p. 64–8.
6.Golz A, Goldenberg D, Netzer A, Westerman LM, Westerman ST,
Fradis M, et al. Cholesteatomas associated with ventilation tube
insertion. Arch Otolaryngol Head Neck Surg 1999; 125(7):
754î7.
7.Herdman R, Wright JL. Grommets and cholesteatoma in chil-
dren. J Laryngol Otol 1988; 102(11): 1000î2.
8.Inglis AF. Tympanostomy tubes. In: Cummings CW, Fredrickson
JM, Harker LA, Krause CJ, Richardson MA, Schuller DE, editors.
Otolaryngology Head and Neck Surgery. 3rd ed. St Louis, Mo:
Mosby–Year Book Inc; 1998. p. 478î87.
9.Schuknecht H. Pathology of the Ear. Cambridge, Mass: Harvard
University Press; 1974.
10.El-Bitar MA, Pena MT, Choi SS, Zalzal GH. Retained ventila-
tion tubes: should they be removed at 2 years? Arch Otolaryn-
gol Head Neck Surg 2002; 128(12): 1357î60.
11.Sapçi T, Uøur G, Karavus A, Aørali N, Akbulut UG. Giant cho-
lesteatoma of the external auditory canal. Ann Otol Rhinol La-
ryngol 1997;106(6): 471î3.
12.Owen HH, Rosborg J, Gaihede M. Cholesteatoma of the external
ear canal: etiological factors, symptoms and clinical findings in
a series of 48 cases. BMC Ear Nose Throat Disord 2006; 6: 16.
13.Heilbrun ME, Salzman KL, Glastonbury CM, Harnsberger HR,
Kennedy RJ, Shelton C. External auditory canal cholesteatoma:
clinical and imaging spectrum. AJNR Am J Neuroradiol 2003;
24(4): 751î
6.
14.Garin P, Degols JC, Delos M. External auditory canal choleste-
atoma. Arch Otolaryngol Head Neck Surg 1997; 123(1): 62î5.
15.Makino K, Amatsu M. Epithelial migration on the tympanic
membrane and external canal. Arch Otorhinolaryngol 1986;
243(1): 39î42.
Received on December 3, 2010.
Revised on March 17, 2011.
Accepted on April 11, 2011.